The mother of a teenager allegedly killed by a man she met on the internet today urged social networking sites to stop people creating false on-line identities.

The body of Ashleigh Hall, 17, was found in a field in Sedgefield, County Durham, on Monday evening, after she told her mother the night before she was staying at a friend's house.

Andrea Hall, 39, of Darlington, said: "I can't blame the internet but it is about time that somebody looked at ways of introducing controls which stop people putting up false pictures and false information."

In her tearful first interview since Ashleigh's death, her mother said: "She was so well loved. We have been inundated with cards and flowers.

"Her friends have never been off the phone."

The single mother urged social networking sites to bring in tighter controls on people creating profiles.

She said: "The people who run Facebook and other social networking sites do have some responsibility for bringing in these controls.

"Everybody knows that the internet can be a dangerous place. We trusted Facebook and she was always told never to add a stranger as a friend.

"I brought her up not to talk to strangers and that applied to the Internet as well.

"She said she would never add a stranger as a friend on Facebook.

"She had about 400 friends on Facebook but she knew every single one of them. We can't imagine how she got to be friends with someone she didn't know."